Honing tool



Patented Jan. 8, 1952 HONIN G TOOL Douglas T. Peden, Ann Arbor, and John E. Kline,

Grosse Pointe Farms, Mich., assignors to Micromatic Hone Corporation, Detroit, Mich., a corporation of Michigan Application May 21, 1947, Serial No. 749,432

Claims. l

This invention relates to honing tools, and particularly to an improved honing tool for use with a device for accurately gaging the inside diameter of a cylinder during the machining cperation and interrupting the operation when a desired diameter has been reached.

This invention relates to and constitutes an improvement of the structure illustrated, described and claimed in U. S. Patent 2,308,355, issued January 12, 1943, and that in the application for U. S. Letters Patent, Serial No. 499,472, led August 21, 1943, now abandoned, both of which were assigned to the assignee of this invention.

In the aforementioned U. S. Patent 2,308,356, a calipering or measuring device is disclosed which directly measures the size of the tool during its operation in a bore, to thereby measure the bore which could be finished to any desired dimension. The abrading members of the honing tool were arranged to directly contact the measuring device at an extremity of the working stroke to actuate the device when the diameter had been reached. It was found that a slight abrading effect occurred as a result of the contact of the gaging element with the abrading material, which necessitated occasional readjustment of the gaging mechanism to compensate therefor.

In the above mentioned patent application, Serial No. 499,472, the necessity for readjusting the gage mechanism was substantially reduced by virtue of providing nonabrading tabs at the extremes of the abrasive stone, which in turn contacted the gaging element so as to interrupt the operation of the machine when the desired diameter has been obtained. It has been found when using the embodiments of the aforementioned patent application for honing cylindrical bores of extremely hard material, in particular, that occasionally the nonabrading tabs at the extremities of the abrasive do not react to-the pressure applied in the same degree as the abrading elements which are honing the cylindrical bore. This results, on occasion, in the diameter of the nonabrading tabs varying slightly from the diameter of the honed cylindrical bore and therefore reflects on the accuracy of the aforementioned measuring arrangement.

It is therefore an object of this invention to provide improved and simplified honing tool and measuring means associated therewith for accurately measuring the diameter of a cylindrical bore during the honing operation.

It is a further object of this invention to provide bore engaging elements independently asso- 2 ciated with the abrasive wearing elements which will accurately gage the diameter of the cylindrical bore regardless of relative compression characteristics of the bore engaging elements.

It is a still further object of this invention to provide a honing tool which can be retracted from a cylindrical bore without the abrasive elements scratching or injuring the surface thereof.

It is a still further object of this invention to provide a honingtool which is simple in construction, inexpensive to manufacture and especially accurate in operation.

These and other objects of this invention will become apparent from the following detailed description taken in conjunction with the accompanying drawing, in which:

Figure 1 is a view, partly in section and partly in elevation, of a honing tool embodying features of this invention;

Fig. 2 is a sectional view of the structure illustrated in Fig. 1, taken along the line 2-2 thereof;

Fig. 3 is a sectional view of the structure illustrated in Fig. 1, taken along the line 3-3 thereof, and

Fig. 4 is a broken view of structure illustrated in Fig.` 3, showing a further form of the invention.

Referring now to the drawing, the cylindrical bore which is to be honed is designated at 5, and the honing tool includes a conventional housing element, generally indicated at 1, adapted to enter the bore. Adjacent the upper end of the housing 1, a driving element 9 is provided. An axially actuatable rod I I passes longitudinally through the center o f the housing 'l and on its upper end has a coupling I3 secured thereto. The honing tool of this invention is adapted to be mounted in a'honing machine of the type illustrated in Patent No. 2,350,527, issued June 6, 1944, and assigned to the assignee of the present invention. As can be seen in that patent, the driving element 9 is held in the honing machine, and the coupling I3 is adjustably connected therein. Due to the construction of the machine of that patent, the entire housing 'l will be reciprocated and rotated thereby and the adjustable rod Il, due to the connection of the coupling I3 within the machine, may be axially adjusted with respect to the housing during the rotation and reciprocation of the tool itself.

Adjacent the lower end of the housing .'I, a plurality of radially spaced openings I5 are provided through the wall thereof which are adapted to receive a plurality of abrasive honing stones, indcated at Il. Additional openings I9 are disposed between some of the openings I in the housing 'i for receiving a set of bore engaging or guide elements 2|. The honing stones |1 have nonabrasive holders 23 secured thereto provided with a sloping inward face. The holder and stone project into one of a plurality of inclined slots 25 radially spaced on the outer periphery of a cylindrieal plug 2.1 slidably fitted into the lower end of the housingV 1. rThe slots 25 are of the same inclination as the holders and denne the periphery of a cone, the base oi which is the diameter of the cylindrical plug 21. The honing stones |1 and holders 23 are disposed within thev slots and are caused to move radially outward when the adjustable rod is moved downwardly. This radial movement is produced by the mated inclined surfaces ofthe slots 25 and the holders 23, and substantial pressure can be exerted therethrough Vto force the honing stones against the cylinder bore. Y

- As can be seen in the drawing, thek guidel elements 2| are of a greater` length than thev honing stones l1, for a reason which'will be hereinafter brought out. rEhe4 vinner faces of the guide elements 2| are inclined and slidably abut an inclined face 29 formed on cam elements 3|. The guide elements 2| may be made of any suitable material such as iibre, metal and the like. It will be noted that the inner Afaces of the cam elements 3| are iiat and disposed against a straight longitudinal face of grooves .33 disposed in the cylindrical plug 21.Y The cam elements slide within the grooves 33 and Vhave upper faces which may be disposed iush with the upper end of the plug 21. Withthis arrangement, the plug 21 and guide elements may be moved with or independently ci each other.

The lower end `ofthe adjustable rod is received in a recess 35 formed in the upper end of the cylindrical plug 21, and secured thereto by a laterally Yextending Vpin 31 or other suitable means. A: iioating clutch or cage element 39 is mounted .on the shaft `within the housing 1 above the plug 21. The element 39 is formed with an annular flange 4| adjacent to its lower end and provided with a` central recess '43. The upper end of the recess is threaded as at and the lower end is provided with an opening 4'! through the lower wall of the element 39 which 4permits the adjustingrod to pass therethrough. 'Surrounding the rod yand seated in the recess 43, is a compression spring 49. Coaxial with the adjustable rod Il kand seated upon the yupper end of the helical .spring 49 fare two .or more friction shoes 5| whose outer peripheries, of conc section, are .inclined downwardly and outwardly as at 53. A cap is threaded into the upper end of the recess 43 and is provided with an opening 5l in the center thereof through which the `Aadjusting rod il passes. The inner Vperiphery of over and may be spaced from the ange 4| when the end of the cam element is engaged by the element 33. A washer 55 is disposed on the top surface of the arms 5i against which the lower end of a helical spring E1 abuts. The spring 61 surrounds the element 35i and is compressed to a desired amount by a collar 69 which is threaded on the outer periphery of the element 33 and abuts against the upper end of the spring 31. In honing operations in which extremely fine surface finishes are to be produced on the workpiece, itv is' recommended that the guide elements maintain the tool bodyi on its axis of rotation as the honing stones are retracted from engagement with the work. inadvertent re-contacting of the. stone with the work is thus prevented, which otherwise might impair the'surface finish of' the latter.Y It is to be understood, however,

' l that this `'function of the guide elements is not necessarily required forgaging purposes and that. therefore, the space between the inwardly ex-V tending hook v33 and iiange il may be omitted,

\ and the cam elements 3i thus be caused to move longitudinally directly in accord with the axial movement of -cage .33. In such instances, the washer 65, spring 61 and collar 69 may be omitted from the structure without detracting from any Vvfunction of the guiding elements except their stabilizing of the hone body immediately prior to the engagement of the stones and the worls surface and immediately subsequent to the retraction of said stones from said work surface.

As seen in Fig. l., positioned above the cylimI drical bore 5', and mounted on the honing ma-t chine, -isga.v gaging device comprising Va bracket 1| which supports a sleeve 13 in alignment with the honing tool which is reciprocated there7 through. -.Either a caliperlike or ringlike gaging element 15 which, when engaged by the guide elements' as will be hereinafter described, will cause the gaging element 15 .to tripa switch 1'! to rinterrupt the Voperation of the machine. `A caliperlike gaging device is described in detail in the aforementioned Patent No. 2,308,359.

In operation, the honing tool is vinserted inte the cylindrical bore .to be honed, 'with the dia-rifi-l eter of the honing stones and the guide members 2| collapsed to a smaller diameter than the bore 5. The diameter of the guides being slightly larger than that `of the stones, will engage the bore first so as to stabilize the tool until the hom the cap 55 is conically complementally inclined,

as at 59, Vtoengage the outer inclined periphery 53 of the shoes 5i so that when the .cap 551s threaded down into the recess 43, against the bias of spring 43, it will press the shoes 5| inwardly against the ,periphery of the adjustable rod H to form a slip clutch .between the rod and the floating cage .33. 1t will .be noted that Ythe lower end of the floating element 39 may abut against both the cylindrical plug 2-1 `and the upper vendof the cam elements 3| `in the extreme collapsed position ofthe tool.

'Each vof the cam elements 3| has an upwardly projecting arm Si having on the upper end an inwardly extending Vhook 63 adapted to 'eXeIld ing stones contact the bore. During this phase, the honing `machine is put into operation causing simultaneous reciprocation and rotation of the housing '1. As the housing 1 rotates, it'likewise causes'thelhoning stones i1 and guide elements 2|, vmounted therein, to rotate therewith. Due to the construction of the honing machine, as afore-V mentioned, the `adjusting rod Il is moved downwardly to cause the honing stones to engage the cylindrical :bore 5 vwith increasing pressure. As the rod Il is pushed downwardly, the honing stones ,I1 will "be forced outwardly against the `wall of the cylindrical bore 5 by the action of the inclined slots 25 in the cylindrical plug 21 on the rear sloping surface of the holders 23. At the same time, the guide elements 2| will be forced outwardly against the wall of the cylindrical bore due to the action of the element 39 carried by the rod von the cam element 3|. The element 33 will continue to move with ,theadjusting rod Il until theV pressure between the cylindrical bore wall and the guide elements 2| vreaches a predetermined amount. At that time, the shoes 5| will slip onthe rod il as the `rod continues to move temori downwardly toapply further movement and pressure on the honing stones I1. During this last movement, the plug 21 will move relative to the flat face on the cam element 3| disposed in the straight slots 33 of the plug. As the` honing stones |1 enlarge the diameter of the bore 5 during the honing operation, the pressure between the guide elements 2| and the bore is maintained by the frictional drag between the shoes I and the rod I I, which causes the clutch element 39 to force the cam elements 3| downwardly, when the plug 21 is moved downwardly, and radially actuate the guide elements against the bore wall until the pressure therebetween again causes the shoes 5I to slip on the rod I I. This engaging and disengaging of the slip clutch occurs periodically during the honing operation, as deter mined by the pressure between the guide elements and the bore wall. In this way, the guide ele ments 2| are kept in engagement with the bore wall so that they axially stabilize the tool and can be used to gage the diameter of the bore. as will be brought out.

As the tool is reciprocated and rotated, the bore wall will be enlarged by the honing stones and the guide elements 2| will enter the gaging device each upward stroke of the tool. The guide elements 2| extend substantially above the upper end of the honing stones I1 so' that they alone may enter the gaging device and operate the switch thereof when expanded to the iinished diameter as set on the gaging device.

In extremely fine nish honing operations, the honing stones I1, at the end of the operation. exert a substantial pressure against the cylinder bore 5. If the tool were withdrawn while the stones were under such a pressure, they may mar the fine nish of the bore wall. In such instances, the complete structure as shown in Fig. 1 is used. incorporating the washer 65, spring 61 and collar` 69 and providing the space between hook 63 and Harige 4I which limits the effective movement of the spring 61 and the corresponding relative axial movement between the plug 21 and the cam members 3| at the surfaces 33. Thus, the guide members 2| are caused to maintain contact with the work surface 5 until the abrading members I1 have had their operating pressure upon the workpiece fully relieved by virtue of the upward movement of the plug 21. During the rst part of this retractive movement of the plug 21, the pressure on the guide elements will not be materially reduced because, as can be seen in Fig. 1, the spring 61 is acting on the hooks 63 of the cam elements 3| and the latter elements will not be moved upward until the flange 4I engages `the bottom surface of the hooks. Thereafter, the elements 2| and stones |1 will be retracted at a uniform rate with the stones collapsed ahead of and further than the guide elements so that the guide elements can prevent the stones from re-contacting and marring the finished bore during withdrawal. The tool is then withdrawn completely' from the bore, and the finished bore can be replaced by a new bore which is then honed in the manner described. Upon applying the tool to the new bore, the spring 61 will retain the cam elements 3| advanced relative to the flange 4I so that the elements 2| will first contact the bore wall ahead of the stones and be set against the wall with the desired stabilizing pressure before the stones are finally adjusted against the bore wall with the continued movement of the rod I I. As the honing operation progresses and the bore becomes enlarged, radial expansion of the guides 2| is kept apace of the said enlargement by the movement of the cams 3| and plug 21 as a unit,` and the contacting pressure of the guides upon the work could never be less than that resulting from the pressure of the spring 61 times the mechanical advantage of the cam angle 29 of the members 3|.

It is apparent to one skilled in mechanical art that the features of this invention may also be used in a combination of bore contacting elements wherein members I1 consist of coarse abrasive and members 2 I of fine abrasive. During the operating phase of full pressure contact of all of said members upon the workpiece, a composite surface finish is produced upon the work but, upon a slight withdrawal of the actuating rod I I, the pressure of the coarse abrasives I1 upon the work is released While the spring E1 is permitted to maintain prolonged pressure upon the fine abrasives 2| and thus produce an improvement in quality of the surface finish beyond said composite finish.

What is claimed is:

l. A tool for honing a cylinder bore, including, a body, a first set of bore engaging elements supported in said body for outward movement, a second set of bore engaging elements supported in said body for outward movement independent of i said first set, plug means slidably mounted within said body and having a plurality of longitudinally extending slots some of which have the bottom walls disposed parallel to the axis of the plug means, others of which have the bottom walls inclined thereto, said slots extending inwardly from the peripheral surface of the plug means, said first set of elements being disposed in said slots having the inclined bottom walls, said slots having the parallel bottom walls supporting said second set of elements, cam. elements engaging said second set of elements when dis-- posed in said slots having parallel bottom walls, single rod-means secured to said plug, and slip clutch means on said rod for engaging said cam elements for permitting additional pressure to be applied to said first set of elements without applying additional force on said second set of elements.

2. In a honing tool having a cylindrical body, a set of radially adjustable abrading elements on said body, a set of radially adjustable non-abrasive elements on said body, said elements of said sets having the inner edges sloping relative to the axis of the body, plug means with the body having surfaces sloping relative to the axis of the body and engaging the sloping surfaces of said set of abrading elements, cam plates in said body movable relative thereto parallel to the axis of the body and having surfaces sloping relative thereto in engagement with the sloping surfaces of the non-abrading elements, an 'actuating element engaging said plug means for moving the plug means along the axis of the body, and clutch means on said actuating element engageable with said cam plates, said clutch means having slip engagement with said actuating element, said plug means and cam plates moving as a unit to adjust both sets of elements radially when said clutch means is moved with said actuating element and said plug means moving independently of said cam plates when said clutch means slips when said actuating element is moved for radially adjusting the set of abrasive elements without ad- .iusting the set of non-abrasive elements.

3. In a honing tool having a cylindrical body, a. set of radially adjustable abrading elements on said body, a set of radially adjustable non-abraassises sive elements on said.1bedy., saidl elements of, said setshaving the inner; edges.- sloping relative to the. axis ef the body, plus, means with the. body havy Y ine surfaces. sloping-relative to. the` axis of the body and engagingv the slqping surfacesk of saidY set of abrading elements, cam plates in said body meyable relative thereto parallel to the axis of the body and slaying" surfaees, sloping relative thereto, in engagement; with tbe sloping surfaces ai the nen-abrading element, ,anY actuating ele,-v4 Inent engaging said plug means for moving the nii-1gY means .alone the axis of the b ody clutch means ensaid actuating element engageable with said sam nietes said Gluten means having slip engagement said: aotnating elementy said plus means and ear-nplates` moving. as a unit to adjust bntn setse elements radially when said eisten means 1s moved with. sai actuating elenier-1tr and said plug, means moving independently of said earn plates. when saidA clutch means. ,slips when said actuating elem-ent is nieve@ for radially adjusting the set of abxasive elements withoutl adjnstng the set `of nonfabrasive elements, and Spring, means between said clutch means 'and said cam- -plates for maintaining said cam platesshi-zted on said pluglmeans when the sets of abrasive elementsA are unconned to. have tbe set, ef non-abrasive. elements adjusted to Va iai-'eer diameter than the diameter of the 11110011.- ned set or abrasive elements 4l. 1nY a `bnrn'ufig tool having aV body, a set of .abrasive elements supported en said body, a eet of, :nonfabrasive elements supported on said body. eam means engaging, said s et ef abrasive elements and shiftable lengthwise of thev body .for

engageable with `said cam plates, when the `cam plates offer. a. offv resistanee te. innver ment, and whien is retained statienary es tbe` d; and pluefmeans. .is moved. 'When the reeis'tanee against movement oi the earn plates inf ereased to a predetermined amount.

5,. In al honing tool having a,V body, a set. 0i abrasive elements supported o n said body, a set of non-abrasivel elements supported on said. body, cam means engaging said set of abrasive elements and shiftable lengthwise of the body for radially adjusting said abrasive elerne,ritsearnj plates shift,- ablalengthwise of theI body withV said earn means and independently theredf; for; radially adjusting said non-abrasive elements, a rod seenred te said cam `ineens and extending from. said body., a clutch elementcircumferentially engagingsaid rod andv having slip engagement therewith, said clutch element being engageable. Awith said'caxn plates, sp1- ing means between said `Glutei-.1 element and said cam plates for applying a predetermined force to the cam plates, for shifting said cam plates, and engaging means on said `cam plates and said clutch element for limiting the expansion of said spring means and theamount of movement of said cam plates produced thereby.

DOUGLAS T. PEDEN. JOHN E. KLINE.

REFERENCES' CITED The :following referencges areY of repid in the file of this patent: y

UNITED' STATES Number NameV Y -Date 1,831,915 'Hnrrn Nov,.=17 ,^1931 1,846,371 Sunnen Feb. 23, 1932 1,900,934 Hudson Mar. 14, 1933 1,934,858 Isom Nov. 14, 1933 1,944,955 Sumner;` Jan. 30, 1934, 2,160,494 Floss jMay 30, 193e 2,195,061 Wallace Mar, 26, 1940 2,229,318 Wallace Jan. 21, 1941 2,263,781 Kline NOV. 25, 1941 2,304,9'e0 K lein Dee. 15, 1942 2,400,430 Mitchell May 14, 1946 

